This post will be focused on how to add additional SQL instance to an existing SQL Server 2008 R2 Cluster. At first I was a little confused about the concept of Active/Active and Active/Passive and its relationship with SQL failover clustering. In a multi failover cluster instances, these terms can be seen as ambiguous when used to describe the configuration of the SQL Server instances and the nodes they are running on.
In our quest to deliver a secured SQL Server 2008 R2 cluster solution, I will continue from my last post Part3 with the installation of SQL Server 2008 R2 SP1. Please note that when installing SQL server 2008 service pack in a cluster, this needs to be installed on the Passive node at any point in time. If this is installed on the Active node, then SQL will require a reboot thereby defeating the purpose of clustering.